Structure of the yeast vacuolar ATPase.
The subunit architecture of the yeast vacuolar ATPase (V-ATPase) was analyzed by single particle transmission electron microscopy and electrospray ionization (ESI) tandem mass spectrometry. A three-dimensional model of the intact V-ATPase was calculated from two-dimensional projections of the complex at a resolution of 25 angstroms. Images of yeast V-ATPase decorated with monoclonal antibodies against subunits A, E, and G position subunit A within the pseudo-hexagonal arrangement in the V1, the N terminus of subunit G in the V1-V0 interface, and the C terminus of subunit E at the top of the V1 domain. ESI tandem mass spectrometry of yeast V1-ATPase showed that subunits E and G are most easily lost in collision-induced dissociation, consistent with a peripheral location of the subunits. An atomic model of the yeast V-ATPase was generated by fitting of the available x-ray crystal structures into the electron microscopy-derived electron density map. The resulting atomic model of the yeast vacuolar ATPase serves as a framework to help understand the role the peripheral stalk subunits are playing in the regulation of the ATP hydrolysis driven proton pumping activity of the vacuolar ATPase.
Zhang
Zhenyu
Z
Department of Biochemistry, University of California, Riverside, California 92521, USA.
Zheng
Yesha
Y
Mazon
Hortense
H
Milgrom
Elena
E
Kitagawa
Norton
N
Kish-Trier
Erik
E
Heck
Albert J R
AJ
Kane
Patricia M
PM
Wilkens
Stephan
S
D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D006868:Hydrolysis; D008958:Models, Molecular; D020836:Protein Structure, Quaternary; D021122:Protein Subunits / Q000737:chemistry* / Q000378:metabolism; D011522:Protons; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D025262:Vacuolar Proton-Translocating ATPases / Q000737:chemistry* / Q000378:metabolism
D021122:Protein Subunits; D011522:Protons; D000255:Adenosine Triphosphate; D025262:Vacuolar Proton-Translocating ATPases